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1.
Environ Pollut ; 345: 123181, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38237850

RESUMO

Sensitivity of bird species to environmental metal pollution varies but there is currently no general framework to predict species-specific sensitivity. Such information would be valuable from a conservation point-of-view. Calcium (Ca) has antagonistic effects on metal toxicity and studies with some common model species show that low dietary and circulating calcium (Ca) levels indicate higher sensitivity to harmful effects of toxic metals. Here we measured fecal Ca and five other macroelement (potassium K, magnesium Mg, sodium Na, phosphorus P, sulphur S) concentrations as proxies for dietary levels in 66 bird species to better understand their interspecific variation and potential use as an indicator of metal sensitivity in a wider range of species (the main analyses include 39 species). We found marked interspecific differences in fecal Ca concentration, which correlated positively with Mg and negatively with Na, P and S levels. Lowest Ca concentrations were found in insectivorous species and especially aerial foragers, such as swifts (Apodidae) and swallows (Hirundinidae). Instead, ground foraging species like starlings (Sturnidae), sparrows (Passeridae), cranes (Gruidae) and larks (Alaudidae) showed relatively high fecal Ca levels. Independent of phylogeny, insectivorous diet and aerial foraging seem to indicate low Ca levels and potential sensitivity to toxic metals. Our results, together with information published on fecal Ca levels and toxic metal impacts, suggest that fecal Ca levels are a promising new tool to evaluate potential metal-sensitivity of birds, and we encourage gathering such information in other bird species. Information on the effects of metals on breeding parameters in a wider range of bird species would also help in ranking species by their sensitivity to metal pollution.


Assuntos
Cálcio , Pardais , Animais , Dieta , Poluição Ambiental/análise , Enxofre
2.
J Intern Med ; 289(1): 12-28, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32656940

RESUMO

Monitoring survival of cancer patients using data collected by population-based cancer registries is an important component of cancer control. In this setting, patient survival is often summarized using net survival, that is survival from cancer if there were no other possible causes of death. Although net survival is the gold standard for comparing survival between groups or over time, it is less relevant for understanding the anticipated real-world prognosis of patients. In this review, we explain statistical concepts targeted towards patients, clinicians and healthcare professionals that summarize cancer patient survival under the assumption that other causes of death exist. Specifically, we explain the appropriate use, interpretation and assumptions behind statistical methods for competing risks, loss in life expectancy due to cancer and conditional survival. These concepts are relevant when producing statistics for risk communication between physicians and patients, planning for use of healthcare resources, or other applications when consideration of both cancer outcomes and the competing risks of death is required. To reinforce the concepts, we use Swedish population-based data of patients diagnosed with cancer of the breast, prostate, colon and chronic myeloid leukaemia. We conclude that when choosing between summary measures of survival it is critical to characterize the purpose of the study and to determine the nature of the hypothesis under investigation. The choice of terminology and style of reporting should be carefully adapted to the target audience and may range from summaries for specialist readers of scientific publications to interactive online tools aimed towards lay persons.


Assuntos
Neoplasias/mortalidade , Neoplasias da Mama/mortalidade , Causas de Morte , Neoplasias do Colo/mortalidade , Feminino , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/mortalidade , Expectativa de Vida , Masculino , Neoplasias da Próstata/mortalidade , Sistema de Registros , Análise de Sobrevida , Suécia/epidemiologia
3.
J Intern Med ; 287(4): 448-454, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31927786

RESUMO

BACKGROUND: The reported incidence of Philadelphia-negative myeloproliferative neoplasms (MPNs) differs substantially between previous reports, likely due to true regional differences in incidence and/or variations in the quality and coverage of the cancer registers. OBJECTIVE: We therefore assessed MPN incidence in Sweden during recent years using prospectively collected information captured in Swedish health registers. METHODS: Patients with MPNs were identified through the Swedish Cancer Register and Swedish Blood Cancer Register between 2000 and 2014. Information on the Swedish population was obtained from the Human Mortality Database. Crude and age-standardized incidence rates of MPNs with 95% confidence intervals (CIs) were calculated. RESULTS: A total of 6281 MPN cases were reported to the Swedish Cancer Register and Swedish Blood Cancer Register during 2000-2014. The age-standardized, to the Swedish population in 2000, incidence for all MPNs was 4.45 (95% confidence interval [CI] 4.34-4.56)/100 000 person-years. The age-standardized incidence for polycythemia vera was 1.48 (1.42-1.54), for essential thrombocythemia 1.60 (1.53-1.66) and for primary myelofibrosis 0.52 (0.48-0.56)/100 000 person-years, respectively. The incidence rate of MPNs was substantially higher in the older compared to the younger age groups. The incidence increased during the study period, likely to do better reporting and increasing age of the general population. CONCLUSION: The reported MPN incidences in our study, which were in the higher interval of previously published studies, are likely more accurate compared to previous reports due to the population-based setting and high level of coverage in the Swedish Cancer and Blood Cancer Registers.


Assuntos
Neoplasias da Medula Óssea/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Policitemia Vera/epidemiologia , Mielofibrose Primária/epidemiologia , Estudos Prospectivos , Sistema de Registros , Suécia/epidemiologia , Trombocitemia Essencial/epidemiologia , Adulto Jovem
4.
Int J Stroke ; 15(5): 467-476, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31679478

RESUMO

The recent advent of endovascular procedures has created the unique opportunity to collect and analyze thrombi removed from cerebral arteries, instigating a novel subfield in stroke research. Insights into thrombus characteristics and composition could play an important role in ongoing efforts to improve acute ischemic stroke therapy. An increasing number of centers are collecting stroke thrombi. This paper aims at providing guiding information on thrombus handling, procedures, and analysis in order to facilitate and standardize this emerging research field.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , Acidente Vascular Cerebral , Trombose , Isquemia Encefálica/complicações , Isquemia Encefálica/cirurgia , Humanos , Acidente Vascular Cerebral/cirurgia , Trombectomia
5.
Cancer Epidemiol ; 60: 168-173, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31054465

RESUMO

There are a broad range of survival-based metrics that are available to report from cancer survival studies, with varying advantages and disadvantages. A combination of metrics should be considered to improve comprehensibility and give a fuller understanding of the impact of cancer. In this article, we discuss the utility of loss in life expectancy and gain in life years as measures of cancer impact, and to quantify differences across population groups. These measures are simple to interpret, have a real-world meaning, and evaluate impact over a life-time horizon. We illustrate the use of the loss in life expectancy measures through a range of examples using data on women diagnosed with cancer in England. We use four different examples across a number of tumour types to illustrate different uses of the metrics, and highlight how they can be interpreted and used in practice in population-based oncology studies. Extensions of the measures conditional on survival to specific times after diagnosis can be used to give updated prognosis for cancer patients. Furthermore, we show how the measures can be used to understand the impact of population differences seen across patient groups. We believe that these under-used, and relatively easy to calculate, measures of overall impact can supplement reporting of cancer survival metrics and improve the comprehensibility compared to the metrics typically reported.


Assuntos
Expectativa de Vida/tendências , Neoplasias/mortalidade , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
6.
Clin Neuroradiol ; 29(4): 775, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31020336

RESUMO

Correction to: Clin Neuroradiol 2019 https://doi.org/10.1007/s00062-019-00776-2 The original version of this article unfortunately contained a mistake. The Acknowledgements were missing. The correct information is given ….

7.
Clin Neuroradiol ; 29(4): 763-774, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30915482

RESUMO

BACKGROUND: Cerebral vasospasm (CVS) following subarachnoid hemorrhage occurs in up to 70% of patients. Recently, stents have been used to successfully treat CVS. This implies that the force required to expand spastic vessels and resolve vasospasm is lower than previously thought. OBJECTIVE: We develop a mechanistic model of the spastic arterial wall to provide insight into CVS and predict the forces required to treat it. MATERIAL AND METHODS: The arterial wall is modelled as a cylindrical membrane using a constrained mixture theory that accounts for the mechanical roles of elastin, collagen and vascular smooth muscle cells (VSMC). We model the pressure diameter curve prior to CVS and predict how it changes following CVS. We propose a stretch-based damage criterion for VSMC and evaluate if several commercially available stents are able to resolve vasospasm. RESULTS: The model predicts that dilatation of VSMCs beyond a threshold of mechanical failure is sufficient to resolve CVS without damage to the underlying extracellular matrix. Consistent with recent clinical observations, our model predicts that existing stents have the potential to provide sufficient outward force to successfully treat CVS and that success will be dependent on an appropriate match between stent and vessel. CONCLUSION: Mathematical models of CVS can provide insights into biological mechanisms and explore treatment approaches. Improved understanding of the underlying mechanistic processes governing CVS and its mechanical treatment may assist in the development of dedicated stents.


Assuntos
Artérias Cerebrais/fisiopatologia , Modelos Cardiovasculares , Stents , Vasoespasmo Intracraniano/terapia , Angioplastia/instrumentação , Angioplastia/métodos , Fenômenos Biomecânicos/fisiologia , Pressão Sanguínea/fisiologia , Matriz Extracelular/fisiologia , Humanos , Músculo Liso Vascular/fisiopatologia , Miócitos de Músculo Liso/fisiologia , Hemorragia Subaracnóidea/complicações , Vasoespasmo Intracraniano/etiologia , Vasoespasmo Intracraniano/fisiopatologia
8.
Diabetes Metab ; 44(4): 354-360, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29861145

RESUMO

AIM: Coffee consumption is inversely related to risk of type 2 diabetes (T2D). In contrast, an increased risk of latent autoimmune diabetes in adults (LADA) has been reported in heavy coffee consumers, primarily in a subgroup with stronger autoimmune characteristics. Our study aimed to investigate whether coffee consumption interacts with HLA genotypes in relation to risk of LADA. METHODS: This population-based study comprised incident cases of LADA (n=484) and T2D (n=1609), and also 885 healthy controls. Information on coffee consumption was collected by food frequency questionnaire. Odds ratios (ORs) with 95% CIs of diabetes were calculated and adjusted for age, gender, BMI, education level, smoking and alcohol intake. Potential interactions between coffee consumption and high-risk HLA genotypes were calculated by attributable proportion (AP) due to interaction. RESULTS: Coffee intake was positively associated with LADA in carriers of high-risk HLA genotypes (OR: 1.14 per cup/day, 95% CI: 1.02-1.28), whereas no association was observed in non-carriers (OR: 1.04, 95% CI: 0.93-1.17). Subjects with both heavy coffee consumption (≥4 cups/day) and high-risk HLA genotypes had an OR of 5.74 (95% CI: 3.34-9.88) with an estimated AP of 0.36 (95% CI: 0.01-0.71; P=0.04370). CONCLUSION: Our findings suggest that coffee consumption interacts with HLA to promote LADA.


Assuntos
Café , Dieta/estatística & dados numéricos , Predisposição Genética para Doença/epidemiologia , Diabetes Autoimune Latente em Adultos/epidemiologia , Idoso , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença/genética , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Resistência à Insulina/genética , Diabetes Autoimune Latente em Adultos/genética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
9.
Diabetes Metab ; 43(6): 536-542, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28669512

RESUMO

BACKGROUND: A family history of diabetes (FHD) is a strong predictor of diabetes risk, yet has rarely been investigated in latent autoimmune diabetes in adults (LADA). This study therefore investigated the risk of LADA and type 2 diabetes (T2D) in relation to FHD, taking into account the type of diabetes in relatives. METHODS: Data from a population-based study were used, including incident cases of LADA [glutamic acid decarboxylase antibody (GADA)-positive, n=378] and T2D (GADA-negative, n=1199), and their matched controls (n=1484). First-degree relatives with disease onset at age<40 years and taking insulin treatment were classified as type 1 diabetes (T1D) or, if otherwise, as T2D. Odds ratios (ORs) were adjusted for age, gender, BMI, education and smoking. Cases were genotyped for high- and low-risk HLA genotypes. RESULTS: Both FHD-T1D (OR: 5.8; 95% CI: 3.2-10.3) and FHD-T2D (OR: 1.9; 95% CI: 1.5-2.5) were associated with an increased risk of LADA, whereas the risk of T2D was associated with FHD-T2D (OR: 2.7; 95% CI: 2.2-3.3), but not FHD-T1D. In LADA patients, FHD-T1D vs FHD-T2D was associated with higher GADA but lower C-peptide levels, lower prevalence of low-risk HLA genotypes (5.0% vs 28.6%, respectively; P=0.038) and a tendency for higher prevalence of high-risk genotypes (90.0% vs 69.1%, respectively; P=0.0576). CONCLUSION: The risk of LADA is substantially increased with FHD-T1D but also, albeit significantly less so, with FHD-T2D. This supports the idea of LADA as a mix of both T1D and T2D, but suggests that the genes related to T1D have greater impact. LADA patients with FHD-T1D had more T1D-like features, emphasizing the heterogeneity of LADA.


Assuntos
Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Autoimune Latente em Adultos/epidemiologia , Anamnese , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Fatores de Risco
10.
Diabet Med ; 34(9): 1259-1263, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28632336

RESUMO

AIM: It has been suggested that experiencing serious life events may promote Type 1 diabetes in children. Studies in adults are lacking, as are studies on the interaction of life events with genetic factors. We aimed to investigate life events and the risk of latent autoimmune diabetes in adults (LADA) and Type 2 diabetes while taking into account HLA genotype. METHODS: Analysis was based on 425 incident cases of LADA, 1417 incident cases of Type 2 diabetes and 1702 population-based controls recruited in Sweden between 2010 and 2016. Self-reported information on life events including conflicts, divorce, illness/accidents, death and financial problems experienced during the 5 years preceding diagnosis/index year was used. Odds ratios (ORs) and 95% confidence intervals (95% CI) were calculated by logistic regression and adjusted for age, sex, BMI, family history of diabetes, smoking, physical activity and education. RESULTS: Overall there was no association between experience of any life event and either LADA (OR 0.86, 95% CI 0.68-1.08) or Type 2 diabetes (OR 1.00, 95% CI 0.83-1.21). The results were similar for individual events as well as in separate analysis of men and women. Similar results were seen in more autoimmune LADA (glutamic acid decarboxylase antibodies > median) [OR (any life event) 0.88, 95% CI 0.64-1.21] and in LADA carriers of the high-risk HLADR4-DQ8 genotype (OR 0.89, 95% CI 0.61-1.29). CONCLUSIONS: Our findings indicate that experience of a serious life event, including the death of a family member, divorce or financial problems, is not associated with an increased risk of LADA, overall or in genetically susceptible individuals.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/etiologia , Diabetes Autoimune Latente em Adultos/epidemiologia , Diabetes Autoimune Latente em Adultos/etiologia , Acontecimentos que Mudam a Vida , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Anamnese/estatística & dados numéricos , Pessoa de Meia-Idade , Fatores de Risco , Suécia/epidemiologia
12.
J Intern Med ; 282(2): 156-163, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28470872

RESUMO

OBJECTIVES: The purpose of this study was to explore the pattern of mortality above the age of 100 years. In particular, we aimed to examine whether Scandinavian data support the theory that mortality reaches a plateau at particularly old ages. Whether the maximum length of life increases with time was also investigated. METHODS: The analyses were based on individual level data on all Swedish and Danish centenarians born from 1870 to 1901; in total 3006 men and 10 963 women were included. Birth cohort-specific probabilities of dying were calculated. Exact ages were used for calculations of maximum length of life. Whether maximum age changed over time was analysed taking into account increases in cohort size. RESULTS: The results confirm that there has not been any improvement in mortality amongst centenarians in the past 30 years and that the current rise in life expectancy is driven by reductions in mortality below the age of 100 years. The death risks seem to reach a plateau of around 50% at the age 103 years for men and 107 years for women. Despite the rising life expectancy, the maximum age does not appear to increase, in particular after accounting for the increasing number of individuals of advanced age. CONCLUSION: Mortality amongst centenarians is not changing despite improvements at younger ages. An extension of the maximum lifespan and a sizeable extension of life expectancy both require reductions in mortality above the age of 100 years.


Assuntos
Expectativa de Vida , Mortalidade , Idoso de 80 Anos ou mais , Dinamarca/epidemiologia , Feminino , Humanos , Masculino , Probabilidade , Suécia/epidemiologia
13.
Biotech Histochem ; 92(1): 46-58, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28157427

RESUMO

WNT5A is a secreted, noncanonical WNT signaling protein that has been reported to promote progression of several types of cancer, including oral squamous cell carcinoma. Many WNT5A antibodies are available commercially for immunohistochemistry (IHC) and western blot analysis. Validation of the primary antibodies, however, is often neglected. We characterized antibodies for detecting WNT5A by IHC and western blot analysis. We evaluated one polyclonal and three monoclonal commercially available WNT5A antibodies. After optimization of the IHC assay, all four antibodies showed cytoplasmic WNT5A expression in tissue samples; in contrast, only one antibody detected WNT5A in western blots. A pre-absorption test with recombinant WNT5A showed that AF645 and 3A4 antibodies specifically detected WNT5A in different assays. We suggest that the monoclonal 3A4 antibody is the most appropriate for use with IHC, while the polyclonal AF645 antibody is the best for western blot analysis.


Assuntos
Anticorpos/imunologia , Proteína Wnt-5a/imunologia , Biomarcadores Tumorais , Western Blotting , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Reprodutibilidade dos Testes , Coloração e Rotulagem , Proteína Wnt-5a/química
14.
J Intern Med ; 281(4): 398-406, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28164394

RESUMO

BACKGROUND: Smoking and nicotine exposure increase insulin resistance and the risk of type 2 diabetes. Swedish smokeless tobacco (snus) is high in nicotine, and its use is prevalent in Scandinavian countries, but few studies have investigated snus use in relation to diabetes risk. OBJECTIVE: To explore the association between snus use and risk of type 2 diabetes using pooled data from five cohorts. METHODS: Analyses were based on prospective studies conducted between 1990 and 2013 including 54 531 never-smoking men and 2441 incident cases of type 2 diabetes identified through screening, self-reporting and hospital and prescription registries. Hazard ratios (HRs) and 95% confidence intervals (CIs) were assessed and adjusted for age, body mass index, educational level, alcohol consumption and physical activity. RESULTS: Compared to never users, the HR of type 2 diabetes was 1.15 (95% CI: 1.00-1.32) in current users of snus. In individuals consuming 5-6 boxes per week, the HR was 1.42 (95% CI: 1.07-1.87); in those consuming ≥7 boxes per week, the HR was 1.68 (95% CI: 1.17-2.41). Each additional box of snus consumed per week yielded an HR of 1.08 (95% CI: 1.01-1.16). CONCLUSION: Our findings indicate that high consumption of snus is a risk factor for type 2 diabetes. The risk was similar to that in smokers, implying that smokers will not reduce their risk of type 2 diabetes by changing to snus use. The results also support the notion that nicotine increases the risk of type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Tabaco sem Fumaça/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fatores de Risco , Suécia/epidemiologia
15.
Diabet Med ; 34(4): 514-521, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27353226

RESUMO

AIMS: It has been suggested that moist snuff (snus), a smokeless tobacco product that is high in nicotine and widespread in Scandinavia, increases the risk of Type 2 diabetes. Previous studies are however few, contradictory and, with regard to autoimmune diabetes, lacking. Our aim was to study the association between snus use and the risk of Type 2 diabetes and latent autoimmune diabetes of adulthood (LADA). METHOD: Analyses were based on incident cases (Type 2 diabetes, n = 724; LADA, n = 200) and population-based controls (n = 699) from a Swedish case-control study. Additional analyses were performed on cross-sectional data from the Norwegian HUNT study (n = 21 473) with 829 prevalent cases of Type 2 diabetes. Odds ratios (OR) were estimated adjusted for age, BMI family history of diabetes and smoking. Only men were included. RESULTS: No association between snus use and Type 2 diabetes or LADA was seen in the Swedish data. For Type 2 diabetes, the OR for > 10 box-years was 1.00 [95% confidence interval (CI), 0.47 to 2.11] and for LADA 1.01 (95% CI, 0.45 to 2.29). Similarly, in HUNT, the OR for Type 2 diabetes in ever-users was estimated at 0.91 (95% CI, 0.75 to 1.10) and in heavy users at 0.92 (95% CI, 0.46 to 1.83). CONCLUSION: The risk of Type 2 diabetes and LADA is unrelated to the use of snus, despite its high nicotine content. This opens the possibility of the increased risk of Type 2 diabetes seen in smokers may not be attributed to nicotine, but to other substances in tobacco smoke.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Autoimune Latente em Adultos/epidemiologia , Uso de Tabaco/epidemiologia , Tabaco sem Fumaça/estatística & dados numéricos , Idoso , Estudos Transversais , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Noruega/epidemiologia , Razão de Chances , Prevalência , Suécia/epidemiologia
16.
Phys Rev Lett ; 117(15): 151302, 2016 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-27768338

RESUMO

A search for dark matter linelike signals iss performed in the vicinity of the Galactic Center by the H.E.S.S. experiment on observational data taken in 2014. An unbinned likelihood analysis iss developed to improve the sensitivity to linelike signals. The upgraded analysis along with newer data extend the energy coverage of the previous measurement down to 100 GeV. The 18 h of data collected with the H.E.S.S. array allow one to rule out at 95% C.L. the presence of a 130 GeV line (at l=-1.5°, b=0° and for a dark matter profile centered at this location) previously reported in Fermi-LAT data. This new analysis overlaps significantly in energy with previous Fermi-LAT and H.E.S.S. RESULTS: No significant excess associated with dark matter annihilations was found in the energy range of 100 GeV to 2 TeV and upper limits on the gamma-ray flux and the velocity weighted annihilation cross section are derived adopting an Einasto dark matter halo profile. Expected limits for present and future large statistics H.E.S.S. observations are also given.

18.
J Thromb Haemost ; 14(12): 2342-2352, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27653814

RESUMO

Essentials Limited data on hemostatic benefits of platelet transfusion (PT) exist. 44 healthy subjects had a single dose of ticagrelor or clopidogrel ± autologous PT post-dosing. PT did not reverse ticagrelor's antiplatelet effects and had minimal impact post clopidogrel. Post-ticagrelor, PT is unlikely to be beneficial, and the benefits post-clopidogrel are unknown. SUMMARY: Background Antiplatelet agents increase bleeding risk. Few data on hemostatic benefits of platelet transfusion exist. Objective To assess the effect of autologous platelet transfusion on ticagrelor-mediated and clopidogrel-mediated platelet inhibition in a single-center, open-label, randomized, cross-over study (NCT01744288). Methods Forty-four healthy subjects received ticagrelor (180 mg) or clopidogrel (600 mg; two functional CYP2C19 alleles [*1 or *17] required) with or without platelet transfusion (14-day washout). Subjects received one autologous platelet apheresis unit (approximately six pooled donor platelet units) 24 h (n = 15) or 48 h (n = 13) after ticagrelor or 48 h after clopidogrel (n = 16). Platelet apheresis was conducted 72 h before transfusion. Aspirin (81 mg per day) was taken from after apheresis until 24 h before transfusion. P2Y12 reaction units (PRUs) and inhibition of platelet aggregation (IPA) induced by ADP were measured. Results Mean age and body mass index were 30 years (standard deviation [SD] 6 years) and 26.9 kg m-2 (SD 4.0 kg m-2 ), respectively; 98% of subjects were men, and 39 of 44 completed treatment. Platelet transfusion 24 h after ticagrelor had minimal effects on IPA or PRU values within 48 h after transfusion. Platelet transfusion 48 h after ticagrelor also had minimal effects on IPA or PRU values at most post-transfusion times. Platelet transfusion 48 h after clopidogrel, versus no transfusion, had a small reversing effect on IPA (24 h, 36 h, and 48 h) and PRU values (12 h, 24 h, and 36 h) after transfusion. Conclusions Autologous platelet transfusion is unlikely to be of clinical benefit in reversing the antiplatelet effects of ticagrelor. The clinical relevance of the small effects seen with clopidogrel is unknown.


Assuntos
Adenosina/análogos & derivados , Plaquetas/efeitos dos fármacos , Transfusão de Plaquetas/métodos , Ticlopidina/análogos & derivados , Adenosina/farmacologia , Adulto , Remoção de Componentes Sanguíneos , Plaquetas/citologia , Índice de Massa Corporal , Estudos de Casos e Controles , Clopidogrel , Estudos Cross-Over , Citocromo P-450 CYP2C19/genética , Feminino , Hemostasia , Humanos , Masculino , Inibidores da Agregação Plaquetária/farmacologia , Antagonistas do Receptor Purinérgico P2Y/farmacologia , Reprodutibilidade dos Testes , Ticagrelor , Ticlopidina/farmacologia , Fatores de Tempo , Adulto Jovem
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